Short Wave Podcast Summary

Episode: Micro Forests: An Emerging Climate Hero?
Date: January 7, 2026
Hosts: Emily Kwong and Regina Barber (Regina not present in this episode)
Producer/Reporter: Rachel Carlson
Guest Experts: Dr. Damian Wollett (Biologist, Loyola Marymount University), Katherine Pokradouni (Horticulturist)

Overview:

This episode explores the concept of "microforests," small, densely planted, human-designed forests in urban environments. Producer Rachel Carlson visits a Los Angeles microforest to uncover how these mini-ecosystems could help cities combat climate change, restore biodiversity, and connect people to nature.

Key Discussion Points & Insights

What is a Microforest? (00:13–02:22)

• Microforests are small-scale, human-engineered forests designed for dense urban spaces.
• Unlike natural forests, they are intentionally planted and use native species tailored to local environments.
• Size: Can range from about 200 square feet up to an acre. The featured L.A. microforest covers 10,000 square feet—the largest in California.

Quote:

“When you plant one tree, that's just a tree. But once you start having the canopy connect, that starts to be what we imagine as a forest.”
— Dr. Damian Wollett (01:36)

• Microforests mimic natural forests with trees whose canopies touch and distinct layers (canopy, shrubs, ground cover).

Origins and Global Spread (04:47–05:11)

• Microforests have roots in Japan, where ecologist Dr. Akira Miyawaki developed this approach more than 50 years ago to restore degraded land.
• The practice has since spread worldwide, including Europe and the U.S.

How to Plant a Microforest (05:11–05:44)

• Diverse species are planted densely and all at once, simulating an entire ecosystem rather than waiting for natural succession.
• Different plant heights and layers are deliberate—the lower layers enhance soil health, while dense growth encourages faster maturity (decades vs. centuries).

Quote:

“You’re kind of planting a whole ecosystem at one time... planting the whole forest at one moment.”
— Dr. Damian Wollett (05:33)

The Los Angeles Microforest: Live Science Experiment (06:16-08:17)

• The LA microforest is two years old and used for scientific experiments.
• Adjacent to it is a control plot (same size, invasive weeds, no intentional planting) for comparison.
• Researchers monitor which animals, insects, and plants appear in each plot.
• Around 100 animal species have been observed in the microforest—matching the total previously recorded in the whole park.

Quote:

“Every two weeks… counting how many insects we're finding, what birds are there, what lizards are moving through there.”
— Dr. Damian Wollett (07:42)

Innovative Biodiversity Research Methods (08:17–10:14)

• Each plant is mapped with a GPS coordinate; drones are used to track plant growth and health.
• Spider webs are collected and analyzed for environmental DNA (eDNA), revealing which animals (even elusive ones like owls and bats) have passed through.

Memorable Moment:

“Spider webs are kind of a filter for the air. And as animals move through … they're shedding skin cells... that sticks to the spider web...”
— Dr. Damian Wollett (08:57)

• Community scientists, via a custom mobile app, contribute data by scanning QR codes on plants to track their growth and health.

Rapid Growth & Community Impact (10:39–11:11; 13:00–13:17)

• Some trees have outpaced similar specimens outside the microforest—a Southern California black walnut grew taller in two years than Damian’s backyard tree did in nearly a decade.
• Over 89% of the plants have survived since planting.

Memorable Moment:
Rachel notes Damian hugging one of the trees:

“He actually hugged the tree at one point, which was maybe my favorite part of the whole day.”
— Rachel Carlson (11:11)

• Visitors are engaged and interested. Several ask questions and express enthusiasm for the microforest as a space for both wildlife and people.

Ecosystem Services & Climate Benefits (11:47–12:52)

• Dense planting crowding out weeds has reduced invasive species by ~80% in two years, compared to the control plot.
• The microforest currently sequesters about one metric ton of carbon per year—anticipated to grow to over 50 metric tons within 20 years (roughly the annual emissions from 10 SUVs).

Quote:

“It’s cooling the neighborhood. It's providing food, again, the insects, the wildlife that's here.”
— Dr. Damian Wollett (12:52)

Notable Quotes & Timestamps

• What Makes a Forest a Forest
  “When you plant one tree, that's just a tree. But once you start having the canopy connect, that starts to be what we imagine as a forest...”
  — Dr. Damian Wollett (01:36)

• Planting a Whole Ecosystem
  “You’re kind of planting a whole ecosystem at one time. Instead of waiting for nature to kind of go through succession...”
  — Dr. Damian Wollett (05:33)

• Spiderweb Science
  “Spider webs are kind of a filter for the air... we collected spiderwebs and... used genetic tools.”
  — Dr. Damian Wollett (08:57)

• Excitement for Rapid Growth
  “He actually hugged the tree at one point, which was maybe my favorite part of the whole day.”
  — Rachel Carlson (11:11)

• Climate Mitigation
  “His lab expects that to increase to over 50 metric tons of carbon dioxide per year in the next two decades. And that's more than the emissions of 10 SUVs.”
  — Rachel Carlson (12:49)

Important Timestamps

• Explanation of Microforests: 00:13–02:22
• Origins & Miyawaki Method: 04:47–05:11
• Dense Layered Planting Discussion: 05:11–05:44
• LA Microforest Field Visit & Biodiversity: 06:16–08:17
• Spider Web DNA Analysis: 08:52–10:14
• Community Science and Rapid Tree Growth: 10:39–11:11
• Weed Suppression & Carbon Capture: 11:47–12:52
• Human Impact and Neighborhood Cooling: 12:52–13:17

Tone and Style

• Lively, curious, and accessible—maintaining a balance of scientific depth and everyday language.
• Moments of light-heartedness, like gentle jokes about “master gardeners” or “for the love of microforest” (13:17).
• Direct engagement with researchers gives the episode a personal, on-the-ground feel.

Takeaway

Microforests are emerging as a dynamic climate solution—boosting urban biodiversity, fostering community involvement, and sequestering carbon. The LA microforest experiment suggests even small slices of forest can have a big impact on both environment and community, providing a hopeful model for climate adaptation in cities.